The caption of this picture says:
(a) Reproduction from Lascaux cave (France), from the Solutrean or early Magdalenian period (∼20,000 kya—picture adapted from ref. 53). (b) Reproduction from the Pergouset cave (France), from the Magdalenian period (17,000 kya—picture adapted from ref. 54)
From Nature Communications, 18 October 2016:
Julien Soubrier, Graham Gower, Alan Cooper
The two living species of bison (European and American) are among the few terrestrial megafauna to have survived the late Pleistocene extinctions. Despite the extensive bovid fossil record in Eurasia, the evolutionary history of the European bison (or wisent, Bison bonasus) before the Holocene (<11.7 thousand years ago (kya)) remains a mystery.
We use complete ancient mitochondrial genomes and genome-wide nuclear DNA surveys to reveal that the wisent is the product of hybridization between the extinct steppe bison (Bison priscus) and ancestors of modern cattle (aurochs, Bos primigenius) before 120 kya, and contains up to 10% aurochs genomic ancestry. Although undetected within the fossil record, ancestors of the wisent have alternated ecological dominance with steppe bison in association with major environmental shifts since at least 55 kya. Early cave artists recorded distinct morphological forms consistent with these replacement events, around the Last Glacial Maximum (LGM, ∼21–18 kya).
See also here.